**************************************************************************
USACE / NAVFAC / AFCEC / NASA
UFGS-26 36 00.00 10 (October 2007)
---------------------------------Preparing Activity: USACE
Superseding
UFGS-26 36 00.00 10 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated July 2016
**************************************************************************
SECTION TABLE OF CONTENTS
DIVISION 26 - ELECTRICAL
SECTION 26 36 00.00 10
AUTOMATIC TRANSFER SWITCH AND BY-PASS/ISOLATION SWITCH
10/07
PART 1
GENERAL
1.1
REFERENCES
1.2
SUBMITTALS
1.3
QUALITY ASSURANCE
1.3.1
Detail Drawings
1.3.2
Switching Equipment
1.4
SITE CONDITIONS
PART 2
PRODUCTS
2.1
STANDARD PRODUCTS
2.2
NAMEPLATE
2.3
AUTOMATIC TRANSFER SWITCH (ATS)
2.3.1
Override Time Delay
2.3.2
Transfer Time Delay
2.3.3
Return Time Delay
2.3.4
Engine Shutdown Time Delay
2.3.5
Exerciser
2.3.6
Auxiliary Contacts
2.3.7
Supplemental Features
2.3.8
Operator
2.3.9
Override Switch
2.3.10
Green Indicating Light
2.3.11
Red Indicating Light
2.4
BY-PASS/ISOLATION SWITCH (BP/IS)
2.4.1
Design
2.4.2
Switch Construction
2.5
ENCLOSURE
2.5.1
Construction
2.5.2
Cleaning and Painting
2.6
TESTING
2.6.1
Factory Testing
2.6.2
Factory Test Reports
2.7
FACTORY TESTING (MEDICAL FACILITIES)
2.7.1
Viewing Ports
SECTION 26 36 00.00 10
Page 1
2.7.2
PART 3
Operating Handles
EXECUTION
3.1
INSTALLATION
3.2
INSTRUCTIONS
3.3
SITE TESTING
3.3.1
Insulation Resistance
3.3.2
Power Failure of Normal Source
3.3.3
Power Failure of Emergency Source
3.3.4
Low Phase-to-Ground Voltage
3.3.5
Operation and Settings
3.3.6
ATS and BP/IS Functions
-- End of Section Table of Contents --
SECTION 26 36 00.00 10
Page 2
**************************************************************************
USACE / NAVFAC / AFCEC / NASA
UFGS-26 36 00.00 10 (October 2007)
---------------------------------Preparing Activity: USACE
Superseding
UFGS-26 36 00.00 10 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated July 2016
**************************************************************************
SECTION 26 36 00.00 10
AUTOMATIC TRANSFER SWITCH AND BY-PASS/ISOLATION SWITCH
10/07
**************************************************************************
NOTE: This guide specification covers the
requirements for low voltage applications of
automatic transfer switches (ATS) and ATS with
by-pass/isolation switches.
Adhere to UFC 1-300-02 Unified Facilities Guide
Specifications (UFGS) Format Standard when editing
this guide specification or preparing new project
specification sections. Edit this guide
specification for project specific requirements by
adding, deleting, or revising text. For bracketed
items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in
respective project, whether or not brackets are
present.
Comments, suggestions and recommended changes for
this guide specification are welcome and should be
submitted as a Criteria Change Request (CCR).
**************************************************************************
PART 1
GENERAL
**************************************************************************
NOTE: This guide specification is for use when the
nature of electrical loads indicates a need for
automatic transfer between two power sources.
Terminology used depends on the application.
"Preferred" and "alternate" should be used when this
specification applies to a stand-by generator system
as defined in NFPA 70. The same terminology should
be used when switching between different sets of
service entrance conductors or between feeders
supplied by different transformers. "Normal" and
"emergency" should be used for the emergency system
application described in NFPA 70.
This specification covers conventional, standard,
SECTION 26 36 00.00 10
Page 3
commercially available equipment appropriate for
most Department of Army/Air Force applications.
Special applications may require synchronized,
closed-transition transfer, or withdrawal features
to facilitate rapid maintenance or repair.
Manufacturers of standard ATS may be able to provide
ATS for special applications. The cost must be
compared with the cost of conventional synchronizing
equipment and circuit breakers with withdrawal
features, as applicable. The decision should be
based on life-cycle costs.
**************************************************************************
1.1
REFERENCES
**************************************************************************
NOTE: This paragraph is used to list the
publications cited in the text of the guide
specification. The publications are referred to in
the text by basic designation only and listed in
this paragraph by organization, designation, date,
and title.
Use the Reference Wizard's Check Reference feature
when you add a Reference Identifier (RID) outside of
the Section's Reference Article to automatically
place the reference in the Reference Article. Also
use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically
be deleted from this section of the project
specification when you choose to reconcile
references in the publish print process.
**************************************************************************
The publications listed below form a part of this specification to the
extent referenced. The publications are referred to within the text by the
basic designation only.
ASTM INTERNATIONAL (ASTM)
ASTM B117
(2016) Standard Practice for Operating
Salt Spray (Fog) Apparatus
INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS (IEEE)
IEEE 602
(2007) Recommended Practice for Electric
Systems in Health Care Facilities - White
Book
IEEE C37.13
(2015) Standard for Low-Voltage AC Power
Circuit Breakers Used in Enclosures
IEEE C37.90.1
(2013) Standard for Surge Withstand
Capability (SWC) Tests for Relays and
Relay Systems Associated with Electric
Power Apparatus
SECTION 26 36 00.00 10
Page 4
IEEE C62.41.1
(2002; R 2008) Guide on the Surges
Environment in Low-Voltage (1000 V and
Less) AC Power Circuits
IEEE C62.41.2
(2002) Recommended Practice on
Characterization of Surges in Low-Voltage
(1000 V and Less) AC Power Circuits
NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)
NEMA ICS 1
(2000; R 2015) Standard for Industrial
Control and Systems: General Requirements
NEMA ICS 10 Part 2
(2005) AC Transfer Equipment, Part 2:
Static AC Transfer Equipment
NEMA ICS 2
(2000; R 2005; Errata 2008) Standard for
Controllers, Contactors, and Overload
Relays Rated 600 V
NEMA ICS 4
(2015) Terminal Blocks
NEMA ICS 6
(1993; R 2011) Enclosures
NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)
NFPA 110
(2016) Standard for Emergency and Standby
Power Systems
NFPA 70
(2014; AMD 1 2013; Errata 1 2013; AMD 2
2013; Errata 2 2013; AMD 3 2014; Errata
3-4 2014; AMD 4-6 2014) National
Electrical Code
U.S. DEPARTMENT OF DEFENSE (DOD)
UFC 3-310-04
(2013) Seismic Design for Buildings
UNDERWRITERS LABORATORIES (UL)
UL 1008
(2014) Transfer Switch Equipment
UL 1066
(2012; Reprint Jul 2013) Low-Voltage AC
and DC Power Circuit Breakers Used in
Enclosures
1.2
SUBMITTALS
**************************************************************************
NOTE: Review submittal description (SD) definitions
in Section 01 33 00 SUBMITTAL PROCEDURES and edit
the following list to reflect only the submittals
required for the project.
The Guide Specification technical editors have
designated those items that require Government
approval, due to their complexity or criticality,
with a "G." Generally, other submittal items can be
reviewed by the Contractor's Quality Control
SECTION 26 36 00.00 10
Page 5
Switching Equipment; G[, [_____]]
Instructions; G[, [_____]]
1.3
1.3.1
QUALITY ASSURANCE
Detail Drawings
Submit interface equipment connection diagram showing conduit and wiring
between ATS and related equipment. Submit schematic, external connection,
one-line schematic and wiring diagram of each ATS assembly. Device,
nameplate, and item numbers shown in list of equipment and material shall
appear on drawings wherever that item appears. Diagrams shall show
interlocking provisions and cautionary notes, if any. Operating
instructions shall be shown either on one-line diagram or separately.
Unless otherwise approved, one-line and elementary or schematic diagrams
shall appear on same drawing.
1.3.2
Switching Equipment
Upon request, manufacturer shall provide notarized letter certifying
compliance with requirements of this specification, including withstand
current rating (WCR). Submit evidence that ATS withstand current rating
(WCR) has been coordinated with upstream protective devices as required by
UL 1008. Submit an operating manual outlining step-by-step procedures for
system startup, operation, and shutdown. Manual shall include
manufacturer's name, model number, service manual, parts list, and brief
description of equipment and basic operating features. Manufacturer's
spare parts data shall be included with supply source and current cost of
recommended spare parts. Manual shall include simplified wiring and
control diagrams for system as installed.
1.4
SITE CONDITIONS
**************************************************************************
NOTE: Provide seismic requirements, if a Government
designer (Corps office or A/E) is the Engineer of
Record, and show on the drawings. Delete the
bracketed phrase if seismic details are not
provided. Pertinent portions of UFC 3-310-04 and
Sections 13 48 00, 13 48 00.00 10 and 26 05 48.00 10,
properly edited, must be included with the contract
documents.
**************************************************************************
Seismic requirements shall be as specified in UFC 3-310-04 and
13 48 00 SEISMIC PROTECTION FOR MISCELLANEOUS EQUIPMENT, 13 48
SEISMIC PROTECTION FOR MECHANICAL EQUIPMENT and 26 05 48.00 10
PROTECTION FOR ELECTRICAL EQUIPMENT [as indicated]. ATS shall
for prolonged performance under following service conditions:
Sections
00.00 10
SEISMIC
be suitable
Altitude
[_____] m feet above mean sea level
Relative Humidity
[_____] percent maximum, continuous
Temperature
Minus [_____] to [_____] degrees C F
SECTION 26 36 00.00 10
Page 7
Switching Equipment; G[, [_____]]
Instructions; G[, [_____]]
1.3
1.3.1
QUALITY ASSURANCE
Detail Drawings
Submit interface equipment connection diagram showing conduit and wiring
between ATS and related equipment. Submit schematic, external connection,
one-line schematic and wiring diagram of each ATS assembly. Device,
nameplate, and item numbers shown in list of equipment and material shall
appear on drawings wherever that item appears. Diagrams shall show
interlocking provisions and cautionary notes, if any. Operating
instructions shall be shown either on one-line diagram or separately.
Unless otherwise approved, one-line and elementary or schematic diagrams
shall appear on same drawing.
1.3.2
Switching Equipment
Upon request, manufacturer shall provide notarized letter certifying
compliance with requirements of this specification, including withstand
current rating (WCR). Submit evidence that ATS withstand current rating
(WCR) has been coordinated with upstream protective devices as required by
UL 1008. Submit an operating manual outlining step-by-step procedures for
system startup, operation, and shutdown. Manual shall include
manufacturer's name, model number, service manual, parts list, and brief
description of equipment and basic operating features. Manufacturer's
spare parts data shall be included with supply source and current cost of
recommended spare parts. Manual shall include simplified wiring and
control diagrams for system as installed.
1.4
SITE CONDITIONS
**************************************************************************
NOTE: Provide seismic requirements, if a Government
designer (Corps office or A/E) is the Engineer of
Record, and show on the drawings. Delete the
bracketed phrase if seismic details are not
provided. Pertinent portions of UFC 3-310-04 and
Sections 13 48 00, 13 48 00.00 10 and 26 05 48.00 10,
properly edited, must be included with the contract
documents.
**************************************************************************
Seismic requirements shall be as specified in UFC 3-310-04 and
13 48 00 SEISMIC PROTECTION FOR MISCELLANEOUS EQUIPMENT, 13 48
SEISMIC PROTECTION FOR MECHANICAL EQUIPMENT and 26 05 48.00 10
PROTECTION FOR ELECTRICAL EQUIPMENT [as indicated]. ATS shall
for prolonged performance under following service conditions:
Sections
00.00 10
SEISMIC
be suitable
Altitude
[_____] m feet above mean sea level
Relative Humidity
[_____] percent maximum, continuous
Temperature
Minus [_____] to [_____] degrees C F
SECTION 26 36 00.00 10
Page 7
Seismic Parameters
PART 2
[_____]
PRODUCTS
**************************************************************************
NOTE: Normally, switched poles should be limited to
three for three-phase, three- or four-wire systems.
Switching of neutral (fourth pole) should only be
considered where emergency/alternate power source is
a separately derived system; where ground potential
at the two voltage sources differs significantly; or
where NFPA 70 requires ground fault protection for
equipment.
Sizing of neutral bus, pole, contacts, and
terminations should consider harmonic currents.
Nonlinear loads such as switch mode power supplies,
electronic ballasts, personal computers, laser
printers, variable frequency motor drives, static
uninterruptible power supplies, and other equipment
described in IEEE 519 and 1100 will produce harmonic
currents with high zero phase sequence components
which are additive in neutral circuit. Neutral
ampere rating may need to be higher than phase
contacts (200 percent is typical for 100 percent
harmonic load).
**************************************************************************
2.1
STANDARD PRODUCTS
Provide material and equipment which are standard products of a
manufacturer regularly engaged in manufacturing the products and that
essentially duplicate items that have been in satisfactory use for at least
2 years prior to bid opening. Submit list of proposed equipment and
material, containing a description of each separate item, and certificates
of compliance showing evidence of UL listing and conformance with
applicable NEMA standards. Such certificates are not required if
manufacturer's published data, submitted and approved, reflect UL listing
or conformance with applicable NEMA standards. The experience use shall
include applications in similar circumstances and of same design and rating
as specified ATS. Equipment shall be capable of being serviced by a
manufacturer-authorized and trained organization that is, in the
Contracting Officer's opinion, reasonably convenient to the site.
2.2
NAMEPLATE
Nameplate showing manufacturer's name and equipment ratings shall be made
of corrosion-resistant material with not less than 3 mm 1/8 inch tall
characters. Nameplate shall be mounted to front of enclosure and shall
comply with nameplate requirements of NEMA ICS 2.
2.3
AUTOMATIC TRANSFER SWITCH (ATS)
**************************************************************************
NOTE: Calculate short-circuit current available at
ATS supply terminals. Caution: emergency source may
be capable of supplying larger amount of
SECTION 26 36 00.00 10
Page 8
short-circuit current. Ampere interrupting capacity
(AIC) rating of circuit protective devices on ATS
supply side should equal or exceed available
short-circuit current. Since ATS WCR should be
equal to or greater than AIC rating of upstream
circuit protective devices, care should be used in
determining available AIC to avoid high costs of
over-rated ATS. WCRs listed in UL 1008 should be
used when fault currents are less than WCR listed.
However, in no case should WCR be less than 10,000
amperes.
Where closed-transition transfer is required,
coordinate system design requirements with power
supplier.
Delete BP/IS requirements if not applicable. Delete
reference to IEEE 602 if not applicable.
**************************************************************************
ATS shall be electrically operated and mechanically held in both operating
positions. ATS shall be suitable for use in [emergency systems] [standby
systems] described in NFPA 70. ATS shall be UL listed. ATS shall be
manufactured and tested in accordance with applicable requirements of
IEEE C37.90.1, IEEE C37.13, IEEE C62.41.1, IEEE C62.41.2, IEEE 602,
NEMA ICS 1, NEMA ICS 2, NEMA ICS 10 Part 2, UL 1008 and UL 1066. ATS shall
conform to NFPA 110. To facilitate maintenance, manufacturer's instruction
manual shall provide typical maximum contact voltage drop readings under
specified conditions for use during periodic maintenance. Manufacturer
shall provide instructions for determination of contact integrity. ATS
shall be rated for continuous duty at specified continuous current rating.
ATS shall be fully compatible and approved for use with BP/IS specified.
BP/IS shall be considered part of ATS system. ATS shall have following
characteristics:
Voltage
[_____] volts [dc] [ac]
Number of Phases
[One] [Two] [Three]
Number of Wires
[Two] [Three] [Four]
Frequency
[25] [50] [60] [400] Hz
Poles
[Two switched] [Three switched] [and solid neutral] [and
switched neutral] [_____]
ATS WCR
Rated to withstand short-circuit current of [_____] amperes,
RMS symmetrical.
Nonwelding Contacts
Rated for nonwelding of contacts when used with upstream
feeder overcurrent devices shown and with available fault
current specified.
SECTION 26 36 00.00 10
Page 9
[Main] [Main and
Neutral] Contacts
2.3.1
Contacts shall have silver alloy composition. [Neutral
contacts shall have same continuous current rating as main or
phase contacts] [Neutral contact continuous current rating
shall be not less than twice the rating of main or phase
contacts].
Override Time Delay
**************************************************************************
NOTE: Consult ATS manufacturers' literature for
feature availability, timing interval range, and
pickup and dropout settings. Insert proper values.
Recommended values for normal applications are shown
in brackets but may be changed for other design
conditions. Where values are not shown or different
settings are required, specify values and settings.
ATS operation should not be initiated during low
voltage conditions attributed to a fault or to
momentary dips or excursions (transients) in normal
or preferred power source. Time delay before
monitored source override should exceed associated
circuit breaker tripping time and normal system
voltage instability periods. Minimum of 1 second is
recommended. Where utility type power source is
used and application is standard, monitoring devices
should drop out at 85 percent of nominal value and
pick up at 90 percent. Where precise power is
monitored, protection should be specified with
monitoring devices set to pick up at 95 and drop out
at 90 percent of nominal. In applications requiring
closer regulation, solid state or microprocessor
arrangement may be used with pickup and dropout
response adjusted as close as 2 percent
differential. However, for these applications a
redundant uninterruptible power supply should be
considered.
Delete generator reference if not required.
**************************************************************************
Provide adjustable time delay to override monitored source deviation from
[0.5] [_____] to [6] [_____] seconds and factory set at [1] [_____]
second[s]. ATS shall monitor phase conductors to detect and respond to
sustained voltage drop of [25] [15] [_____] percent of nominal between any
two [normal] [preferred] source conductors and initiate transfer action to
[alternate] [emergency] source and start engine driven generator after set
time period. Pickup voltage shall be adjustable from [85] [_____] to 100
percent of nominal and factory set at [90] [_____] percent. Dropout
voltage shall be adjustable from [75] [_____] to [98] [_____] percent of
pickup value and factory set at [85] [_____] percent of nominal.
2.3.2
Transfer Time Delay
**************************************************************************
SECTION 26 36 00.00 10
Page 10
NOTE: Use nonzero setting where multiple ATS
require staggered application of load steps to
alternate or emergency source.
**************************************************************************
Time delay before transfer to [alternate] [emergency] power source shall be
adjustable from [0] [_____] to [5] [_____] minutes and factory set at [0]
[_____] minutes. ATS shall monitor frequency and voltage of [alternate]
[emergency] power source and transfer when frequency and voltage are
stabilized. Pickup voltage shall be adjustable from [85] [_____] to 100
percent of nominal and factory set at [90] [_____] percent. Pickup
frequency shall be adjustable from [90] [_____] to 100 percent of nominal
and factory set at [90] [_____] percent.
2.3.3
Return Time Delay
Time delay before return transfer to [normal] [preferred] power source
shall be adjustable from [0] [_____] to [30] [_____] minutes and factory
set at [30] [_____] minutes. Time delay shall be automatically defeated
upon loss or sustained undervoltage of [alternate] [emergency] power
source, provided that [normal] [preferred] supply has been restored.
2.3.4
Engine Shutdown Time Delay
**************************************************************************
NOTE: Omit this paragraph if there is no generator
in transfer scheme. Consult ATS manufacturers'
literature for feature availability, timing interval
range, and pickup and dropout settings. Insert
proper values. Recommended values for normal
applications are shown in brackets but may be
changed for other design conditions. Where values
are not shown or different settings are required,
specify values and settings.
**************************************************************************
Time delay shall be adjustable from [0] [_____] to [30] [_____] minutes and
shall be factory set at 10 [_____] minutes.
2.3.5
Exerciser
**************************************************************************
NOTE: Use this paragraph when automatic system
exercising is required by nature of loads and
desired reliability. Automatic system exerciser is
recommended when diesel engine driven generator set
is used, but only if automatic feature is manually
initiated and can be manually overridden during
exercise period to return ATS to normal or preferred
source. Omit this paragraph if there is no
generator in transfer scheme.
Consult ATS manufacturers' literature for feature
availability, timing interval range, and pickup and
dropout settings. Insert proper values for
application.
**************************************************************************
Provide a generator exerciser timer.
Run times shall be user
SECTION 26 36 00.00 10
Page 11
programmable. The generator exerciser shall be selectable between load
transfer and engine run only, and shall have a fail-safe feature that will
retransfer the ATS to [normal] [preferred] during the exercise period.
2.3.6
Auxiliary Contacts
[Two] [_____] normally open and [two] [_____] normally closed auxiliary
contacts rated at [10][15][_____] amperes at [120][480][_____] volts shall
operate when ATS is connected to [normal] [preferred] power source, and
[two] [_____] normally open and [two] [_____] normally closed contacts
shall operate when ATS is connected to [alternate] [emergency] source.
2.3.7
Supplemental Features
**************************************************************************
NOTE: Delete features when not required. Delete
in-phase monitor unless required to eliminate or
reduce transients during switching of large
inductive loads while limiting time delays
associated with ATS transfer in both directions.
**************************************************************************
ATS shall be furnished with the following:
a.
Engine start contact.
b.
[Alternate] [Emergency] source monitor.
c.
Test switch to simulate normal power outage.
d.
Voltage sensing. Pickup voltage adjustable from 85 to 100 percent of
nominal; dropout adjustable from 75 to 98 percent of pickup.
e.
Time delay bypass switch to override return time delay to normal.
f.
Manual return-to-normal switch.
g.
Means shall be provided in the ATS to insure that motor/transformer
load inrush currents do not exceed normal starting currents. This
shall be accomplished with either in-phase monitoring, time-delay
transition, or load voltage decay sensing methods. If manufacturer
supplies an in-phase monitoring system, the manufacturer shall indicate
under what conditions a transfer cannot be accomplished. If the
manufacturer supplies a time-delay transition system, the manufacturer
shall supply recommendations for establishing time delay. If load
voltage decay sensing is supplied, the load voltage setting shall be
user programmable.
2.3.8
Operator
Manual operator conforming to UL 1008 shall be provided, and shall
incorporate features to prevent operation by unauthorized personnel. ATS
shall be designed for safe manual operation under full load conditions. If
manual operation is accomplished by opening the door, then a dead-front
shall be supplied for operator safety.
2.3.9
Override Switch
**************************************************************************
SECTION 26 36 00.00 10
Page 12
NOTE: Override switch allows operator to switch
load from primary source to alternate or emergency
source and keep it connected to that source. It is
useful for users who prefer alternate or emergency
source under certain operating conditions, such as
lightning storms or during maintenance on primary
source. Override switch will be specified only when
nature of mission and operators' expertise make it
desirable to control power source. User must ensure
that adequate administrative and operational
controls exist to prevent load from being
inadvertently left in alternate or emergency mode.
This paragraph should be omitted for ordinary
applications since override switch significantly
alters ATS function.
**************************************************************************
Override switch shall bypass automatic transfer controls so ATS will
transfer and remain connected to [alternate] [emergency] power source,
regardless of condition of [normal] [preferred] source. [If [alternate]
[emergency] source fails and [normal] [preferred] source is available, ATS
shall automatically retransfer to [normal] [preferred] source.]
2.3.10
Green Indicating Light
A green indicating light shall supervise/provide [normal] [preferred] power
source switch position indication and shall have a nameplate engraved
[NORMAL] [PREFERRED].
2.3.11
Red Indicating Light
A red indicating light shall supervise/provide [alternate] [emergency]
power source switch position indication and shall have a nameplate engraved
[ALTERNATE] [EMERGENCY].
2.4
BY-PASS/ISOLATION SWITCH (BP/IS)
**************************************************************************
NOTE: Omit this section if no by-pass/isolation
switch is required. Delete reference to generator
starting where a generator is not used as alternate
source.
**************************************************************************
2.4.1
Design
Bypass/isolation switch (BP/IS) shall permit load by-pass to either
[normal] [preferred] or [alternate] [emergency] power source and complete
isolation of associated ATS, independent of ATS operating position. BP/IS
and associated ATS shall be products of same manufacturer and shall be
completely interconnected and tested at factory and at project site as
specified. BP/IS shall be manufactured, listed, and tested in accordance
with paragraph AUTOMATIC TRANSFER SWITCH (ATS) and shall have electrical
ratings that exceed or equal comparable ratings specified for ATS.
Operating handles shall be externally operated and arranged so that one
person can perform the bypass and isolation functions through the operation
of a maximum of two handles within 5 seconds. The ATS shall have
provisions for locking in the isolation position. Handle for manual
operation shall be permanently attached to operating mechanism. BP/IS
SECTION 26 36 00.00 10
Page 13
operation shall be accomplished without disconnecting switch load terminal
conductors. Isolation handle positions shall be marked with engraved
plates or other approved means to indicate position or operating condition
of associated ATS, as follows:
a.
Indication shall be provided to show that ATS section is providing
power to the load.
b.
Indication shall be provided of ATS isolation. The ATS controls shall
remain functional with the ATS isolated or in bypass mode to permit
monitoring of the normal power source [and automatic starting of the
generator in the event of a loss of the normal power source]. In the
isolated mode, the bypass section shall be capable of functioning as a
manual transfer switch to transfer the load to either power source.
The ATS shall be capable of undergoing functional operation testing
without service interruption. The ATS may also be completely removed
from the enclosure, if required for maintenance or repair, while the
bypass section continues to power the load.
2.4.2
Switch Construction
Bypass/isolation switch shall be constructed for convenient removal of
parts from front of switch enclosure without removal of other parts or
disconnection of external power conductors. Contacts shall be as specified
for associated ATS, including provisions for inspection of contacts without
disassembly of BP/IS or removal of entire contact enclosure. To facilitate
maintenance, manufacturer shall provide instructions for determination of
contact integrity. BP/IS and associated ATS shall be interconnected with
suitably sized copper bus bars silver-plated at each connection point, and
braced to withstand magnetic and thermal forces created at WCR specified
for associated ATS.
2.5
ENCLOSURE
**************************************************************************
NOTE: Designer must provide normal power source to
ATS when specifying enclosure heater.
If ATS assembly is provided, equipment should be
installed in free-standing, floor-mounted enclosure
as specified, except when manufacturer incorporates
switch specified in wall-mounted enclosure as
standard construction. However, in some
applications it is advisable to specify that ATS or
BP/IS components be mounted in separate switchboard,
switchgear, motor control center, or other
enclosure. Designer shall investigate conditions
and options and specify accordingly.
**************************************************************************
ATS and accessories shall be installed in [wall-mounted] [free-standing,
floor-mounted], [ventilated] [unventilated] NEMA ICS 6, Type [1] [3R] [4]
[12], smooth sheet metal enclosure constructed in accordance with
applicable requirements of UL 1066 and/or UL 1008. [Intake vent shall be
screened and filtered. Exhaust vent shall be screened.] [Door shall have
suitable hinges, locking handle latch, and gasketed jamb.]
[Thermostatically controlled heater shall be provided within enclosure to
prevent condensation over temperature range stipulated in paragraph SERVICE
CONDITIONS.] Metal gauge shall be not less than No. 14. Enclosure shall
SECTION 26 36 00.00 10
Page 14
be equipped with at least two approved grounding lugs for grounding
enclosure to facility ground system using No. [4] [_____] AWG copper
conductors. Factory wiring within enclosure and field wiring terminating
within enclosure shall comply with NFPA 70. If wiring is not color coded,
wire shall be permanently tagged or marked near terminal at each end with
wire number shown on approved detail drawing. Terminal block shall conform
to NEMA ICS 4. Terminals shall be arranged for entrance of external
conductors from [top] [bottom] [top and bottom] of enclosure as shown.
Main switch terminals, including neutral terminal if used, shall be
pressure type suitable for termination of external [copper] [aluminum]
conductors shown.
2.5.1
Construction
Enclosure shall be constructed for ease of removal and replacement of ATS
components and control devices from front without disconnection of external
power conductors or removal or disassembly of major components. Enclosure
of ATS with BP/IS shall be constructed to protect personnel from energized
BP/IS components during ATS maintenance.
2.5.2
Cleaning and Painting
Both the inside and outside surfaces of an enclosure, including means for
fastening, shall be protected against corrosion by enameling, galvanizing,
plating, powder coating, or other equivalent means. Protection is not
required for metal parts that are inherently resistant to corrosion,
bearings, sliding surfaces of hinges, or other parts where such protection
is impractical. Finish shall be manufacturer's standard material, process,
and color and shall be free from runs, sags, peeling, or other defects. An
enclosure marked Type 1, 3R, 4 or 12 shall be acceptable if there is no
visible rust at the conclusion of a salt spray (fog) test using the test
method in ASTM B117, employing a 5 percent by weight, salt solution for 24
hours. Type 4X enclosures are acceptable following performance of the
above test with an exposure time of 200 hours.
2.6
TESTING
Submit a description of proposed field test procedures, including proposed
date and steps describing each test, its duration and expected results, not
less than [_____] weeks prior to test date. Submit certified factory and
field test reports, within 14 days following completion of tests. Reports
shall be certified and dated and shall demonstrate that tests were
successfully completed prior to shipment of equipment.
2.6.1
Factory Testing
A prototype of specified ATS shall be factory tested in accordance with
UL 1008. In addition, factory tests shall be performed on each ATS as
follows:
a.
Insulation resistance test to ensure integrity and continuity of entire
system.
b.
Main switch contact resistance test.
c.
Visual inspection to verify that each ATS is as specified.
d.
Mechanical test to verify that ATS sections are free of mechanical
hindrances.
SECTION 26 36 00.00 10
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e.
2.6.2
Electrical tests to verify complete system electrical operation and to
set up time delays and voltage sensing settings.
Factory Test Reports
Manufacturer shall provide three certified copies of factory test reports.
2.7
FACTORY TESTING (MEDICAL FACILITIES)
**************************************************************************
NOTE: The factory tests sequence listed below is
required for Medical Facilities only.
**************************************************************************
The factory tests for ATS and By-Pass/Isolation switches used in medical
facilities shall be conducted in the following sequence:
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
l.
m.
n.
o.
2.7.1
General
Normal
Overvoltage
Undervoltage
Overload
Endurance
Temperature Rise
Dielectric Voltage-Withstand
Contact Opening
Dielectric Voltage-Withstand (Repeated)
Withstand
Instrumentation and Calibration of High Capacity
Closing
Dielectric Voltage-Withstand (Repeated)
Strength of Insulating Base and Support
Viewing Ports
ATS and BP/IS switches shall be of draw-out construction. Viewing ports to
inspect the contacts without requiring disassembly shall be provided.
2.7.2
Operating Handles
The operating handles shall be externally operated, and designed and
constructed not to stop in an intermediate or neutral position during
operation, but shall permit load by-pass and transfer switch isolation in
no more than two manual operations which can be performed by one person in
5 seconds or less. The transfer speed will be independent of the
operational speed of the switch handle or handles.
PART 3
3.1
EXECUTION
INSTALLATION
ATS shall be installed as shown and in accordance with approved
manufacturer's instructions. Submit dimensioned plans, sections and
elevations showing minimum clearances, weights, and conduit entry
provisions for each ATS.
SECTION 26 36 00.00 10
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3.2
INSTRUCTIONS
Manufacturer's approved operating instructions shall be permanently secured
to cabinet where operator can see them. One-line and elementary or
schematic diagram shall be permanently secured to inside of front enclosure
door. Submit [6] [_____] copies of operating and [6] [_____] copies of
maintenance manuals listing routine maintenance, possible breakdowns,
repairs, and troubleshooting guide.
3.3
SITE TESTING
**************************************************************************
NOTE: Design should incorporate ATS testing in
overall test of complete emergency system under
load, including ATS and generators. Delete BP/IS
reference if not required.
**************************************************************************
Following completion of ATS installation and after making proper
adjustments and settings, site tests shall be performed in accordance with
manufacturer's written instructions to demonstrate that each ATS functions
satisfactorily and as specified. Advise Contracting Officer not less than
5 working days prior to scheduled date for site testing, and provide
certified field test reports within 2 calendar weeks following successful
completion of site tests. Test reports shall describe adjustments and
settings made and site tests performed. Minimum operational tests shall
include the following:
3.3.1
Insulation Resistance
Insulation resistance shall be tested, both phase-to-phase and
phase-to-ground.
3.3.2
Power Failure of Normal Source
Power failure of normal source shall be simulated by opening upstream
protective device. This test shall be performed a minimum of five times.
3.3.3
Power Failure of Emergency Source
Power failure of emergency source with normal source available shall be
simulated by opening upstream protective device for emergency source. This
test shall be performed a minimum of five times.
3.3.4
Low Phase-to-Ground Voltage
Simulate low phase-to-ground voltage for each phase of normal source.
3.3.5
Operation and Settings
Verify operation and settings for specified ATS features, such as override
time delay, transfer time delay, return time delay, engine shutdown time
delay, exerciser, auxiliary contacts, and supplemental features.
3.3.6
ATS and BP/IS Functions
Verify mannual and automatic ATS and BP/IS functions.
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SECTION 26 36 00.00 10
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